Apparatus for concentrating sulphuric acid



April 25, 1939. J. BACHI APPARATUS FOR CONCENTRATING SULPHURIC ACID Filed Nov. 2,*1936 2 Sheets-Sheet l .wo mvCLBl INVENTOR John Bach/ ATTORNEY Apri] 25, 1939. BACI-1| 2,155,633

APPARATUS FOR CONCENTRATING SULPHURIG ACIDA Filed Nov. 2, 1936 2 Sheets-Sheet 2 INVENTOR I .John ach/ ATTORNEY Patented Apr. 25, 1939 PATENT OFFICE APPARATUS FOR CONCEN TRATIN G SULPHURIC ACID John Bachi, Whiting, Ind., assigner to Standard Oil Company, Chicago, Ill., a corporation of Indiana Application November 2, 1936, Serial No. 108,755

2 Claims.

The present invention relates to the concentration of sulphuric acid and relates more particularly to the treating of sludge acids or separated sludge acids obtained in the refining of petroleum oils or their fractional distillates.

In the use of multiple stage acid concentrators of the general type shown in the patent to Heckenbleikner 1,991,745, granted February 19, 1935', it has been found that the practice of using Duriron downcorner pipes for introducing the hot gases into the different stagesparticularly the weak stageresults in the breakage of a large number of these pipes. The frequent breakage of these Duriron downcomer pipes is attributed to the impact of coke thereagainst. This coke forms in the weak stage due to decomposition of sulphonic acids and tar. Duriron pipes are very expensive and their replacement involves a considerable loss of time. The frequent replacement of downcomer pipes has thus become a large factor in lowered eiliciency of operation.

It is a particular object of the present invention to provide an acid concentrating vessel with an improved means for causing contact between the hot gases introduced into the vessel and the liquid contained therein.

It is a further particular object of the present invention to provide an improved arrangement which will take the place of the'conventional Duriron downcomer pipes, particularly in the weak stage of an acid concentrator.

My invention will now be described more particularly with reference to the accompanying drawings in which:

Figure 1 is a top plan view of the concentrator embodying my invention;

Figure 2 is an elevation of a transverse crosssection of the apparatus shown in Figure l showing the auxiliary wall of my invention;

Figure 3 is a cross-section taken on line 3-3 of Figure 2; and

Figures 4 and 5 are cross-sections showing two modified forms of auxiliary wall.

Referring particularly to Figures 1 and 2, I have illustrated a furnace I, a strong acid chamber 2 and a weak acid chamber 3, disposed in series relation, together with conduits 4, 5 and 6, for conducting hot gases overhead from the furnace into said respective acid chambers. An exhaust conduit 'I leads from the weak acid chamber to the conventional Cottrell precipitator (not shown). Suitable conduits 8, 9 and I0 are provided for introducing acid to and withdrawing acid from the respective vessels and for maintaining a definite liquid level therein; The two acid chambers are closed vessels except for openings providing for reception of the above referred to conduits. The specific contruction of the apparatus thus far described may take the form shown in the patent to Heckenbleikner, comprising a horizontal cylindrical or drum shaped steel tank I! provided with a lining of acid proof masonry I2. The drum or shell is divided into two separate chambers 2 and 3 by means of an integrally formed separating wall I3. This results in two vessels deiined by enclosing walls and disposed in series relationship, the separating wall being common to both vessels. The furnace delivers hot gases to a pair of conduits 4 and 5, one of which, 5, extends directly to the weak acid stage and delivers these gases into the first vapor space 2l of the weak acid stage. The other conduit extends directly into the strong acid stage where the gases are caused to bubble through the strong acid. The gases then pass to the irst vapor space 2| of the weak acid stage through the overhead conduit t. Valve means are provided for determining distribution of the gases delivered from the furnace to each of the above two conduits. The arrangement so far den scribed is conventional.

Again referring to Figure 2, it will be seen that I have provided an auxiliary wall lll in combination with the `delining walls of the weak acid vessel. This wall is formed as a continuation of the acid proof masonry lining l2 and extends entirely across the vessel and divides the vapor space above the liquid level into two chambers. This wall extends below the surface of the liquid and presents a transverse linear baiile edge I5 to the passage of gases from the vapor space on one side to the vapor space on the opposite side of the wall, all of the gases passing in the direction indicated by the arrows. This wall is not subject to breakage as are the Duriron downcomer pipes shown in the Heckenbleikner patent, since this wall is more rigidly supported within the vessel, i. e., formed integral with the acid prooi masonry lining and extending completely across the vessel as shown in Figures 3, 4 and 5. The provision of this auxiliary wall Ill in combination with the enclosing walls of the acid vessel makes it unnecessary to replace the broken Duriron downcomer pipe shown in Figure 2.

In Figure 3 I have shown in greater detail the auxiliary wall Ill of Figure 2. A masonry wall is shown supported by a masonry arch I6. A relatively large radius is employed for the supporting arch I6 in order that the lower face I5 thereof present a substantially horizontal baie edge to the passage of gases therebeneath.

Figure 4 shows an alternative form of baiile Wall. The masonry work is supported by a Duriron member Il which engages the opposite walls of the vessel and which is reinforced by a second Duriron member I8, which in turn supports the rst Duriron membei` near its mid-portion.

Figure 5 is another alternative form of construction for my auxiliary wall. In this modi cation, the auxiliary wall extends all the wav to the bottom of the vessel, but is constructed with openings I9 therein, which openings present a baffle edge 2G below the surface of the liquid for the purpose already noted.

I have illustrated my auxiliary wall as being constructed of acid proof brick (Figures 3 and 5) or acid proof brick and Duriron supporting means (Figure 4) but it is apparent that any well-known material which has the necessary strength and acid-resisting characteristics may be employed. Obviously other specific forms of constructing this wall to give the resulting baffle edge disclosed may be employed without departing from the spirit of my invention.

In the operation of my acid concentrator all of the hot gases delivered to the first Vapor space 2| in the weak acid chamber are forced to bubble through the liquid and under the baille edge l5 of the auxiliary wall, and hence into the second vapor space 22 on the opposite side of the auxiliary wall. From this vapor space the hot gases pass by way of a conduit to a Cottrell precipitator (not shown).

It will be seen that I have provided an improvement in acid concentrating apparatus which makes it possible to eliminate the expensive Duriron downcomer pipes. This improved arrangement may be added to present apparatus without modifying its existing structure. The auxiliary wall which I have disclosed effects a more extensive and even distribution of contact between the hot gases and the liquids. This larger area of contact results in a reduction of the blower pressure necessary to force a given Volume of gas through the vessel. The new and improved results thus effected mean a marked increase in efciency of operation.

While I have described my invention in connection with certain specific embodiments thereof, it is to be understood that these embodiments are oered by way of illustration, rather than by way of limitation, and that I do not mean to be limited thereby except as indicated in the scope of the appended claims which should be construed as broadly as the prior art will permit.

I claim: 1

1. Acid concentrating apparatus including va furnace stage and a plurality of concentrating stages, conduit means for directing ho-t gases from said furnace stage successively to said concentrator stages in series, conduit means for conducting the gases from the vapor space of each concentrator stage to the vapor space of the succeeding stage, additional conduit means for bypassing a portion of the hot gases from the furnace stage directly to the Vapor space of a subsequent stage beyond the first of said series stages, means in said subsequent stage forming a confined space above the acid levei for the reception oi' both said series stream and said bypass stream, said means comprising an auxiliary baie wall composed of acid-resisting material extending completely across the interior of said stage and presenting a linear baille edge below the surface of the acid, said bale edge being effective to produce intimate and extensive contact between said gases and said acid.

2. Acid concentrating apparatus including a furnace stage for heating a supply of gases under pressure, a concentrator stage containing relatively strong acid, a concentrator stage containing relatively weak acid, conduit means for directing hot gases from said furnace stage to said strong acid concentrator stage, conduit means for conducting gases from the vapor space of the strong acid stage to the vapor space of the weak acid stage, additional conduit means for bypassing a portion of the hot gases from said furnace stage directly to the vapor space of said weak acid stage, means in said Weak acid stage forming a receiving space above the acid level for the re ception of both said series stream and said bypass stream, said means comprising an auxiliary baffle wall composed of acid resisting material extending completely across the interior of said stage and presenting a linear baille edge below the surface of the acid, said baiiie edge being effective to produce intimate and extensive contact between said gases and said acid.

JOHN BACI-II. 

